[impl_gateway] fix wrong item name of permit join command (#843)

Author: secretmikut

middleware/linkkit/sdk-c/src/services/linkkit/dm/linkkit_gateway_legacy.h

@@ -17,8 +17,8 @@
 #define LINKKIT_GATEWAY_LEGACY_KEY_PROPERTYID  "propertyid"
 #define LINKKIT_GATEWAY_LEGACY_KEY_EVENTID     "eventid"
 #define LINKKIT_GATEWAY_LEGACY_KEY_PAYLOAD     "payload"
-#define LINKKIT_GATEWAY_LEGACY_KEY_PRODUCT_KEY "product_key"
-#define LINKKIT_GATEWAY_LEGACY_KEY_TIMEOUT     "timeout"
+#define LINKKIT_GATEWAY_LEGACY_KEY_PRODUCT_KEY "productKey"
+#define LINKKIT_GATEWAY_LEGACY_KEY_TIMEOUT     "time"
 #define LINKKIT_GATEWAY_LEGACY_KEY_VERSION     "version"
 
 #define LINKKIT_GATEWAY_LEGACY_SYNC_DEFAULT_TIMEOUT_MS (10000)
@@ -61,4 +61,4 @@ typedef struct {
 }linkkit_gateway_legacy_ctx_t;
 
 
-#endif
+#endif